Art of signaling through space.



f;& M dw No. 818,363. PATENTED APR. 17, 1906.

Y 0. D. EHRET. ART OF SIGNALING THROUGH SPACE.

APPLICATION FILED AUG. 25, 1905.

A /L I L, Li I Q UNIT-ED STATES PATENT curios.

coRNEm s D. EHRET, or 'ARDMO'RE, PENNSYLVANIA. Ala-roe sleuAuue THROUGHSPACE.

, Specification of Letters Patent.

Patented April 17, 1906.

' Original application filed July 27, 1903, Serial No. 167,129. iDividedand this application filed August 25, 1906. Serial No. 276,760-

.To all, whom it may concern.-

Be it known that I, CORNELIUS D. EnnE'r, a citizen of the United States,residing at Ardmore, in the county of Montgome and State ofPennsylvania, have invente new and useful Improvements in the Art ofSignaling Throuig1 Space, of which the followin is a speci cation.

y invention relates to electrical signaling, more especially that systemin which electroradiant energy representing the signal or message istransmitted through the natural media.

My invention consists in a method of transforming electroradiant energyinto the energy of electric currents, such electric currents causing orcontrolling the production of an series force electric current of thefluctuating or alternating type and having a frequency corresponding tothe frequency of the transmitted wavetrains and boosting or reinforcingthe alternating current so produced to more effectively control oractuate a receiver or other translating device.

I Reference is to be had to the accompanyin drawings, in which- 'gure 11s a diagrammatic view of the circuits of a transmitting apparatus forimpressing upon the natural media two series of wave-trains, the trainsof each series being dis lacedintime with respect to each other and thefrequency orperiodicity of the electromagnetic waves forming the trainsat one eing different from the periodicity or frequency of theelectromagnetic waves forming the trains of the other series. Fig. 2

is a diagrammatic view of the circuit arrangements at areceivlng-station wherein the received electroradiant energy causes orcontrols the production of a fluctuating or alternating current, suchalternating or fluctuating current being reinforced orboosted. Fig. 3 1sa diagrammatic viewof receiving-circuits in which dephased wave-trainscause or control the production of fluctuating or alternatin currents,such currents being reinor boosted. Referring to Fig. 1, P and P areprimary coils of two separate transformers, such primary windings beingincluded in the circuit of a source of twohased currents-that is, thecurrent passing t oughthe winding P the rimaries P and P. S is thesecondary win in ofthe transformer whose primary 1s P, and S is thesecondary of the transformer whose primary is P. Both of thesetransformers are preferably step-up transformers, the volta es of thesecondaries being preferably equa G is a spark-gap in shunt to thesecondary S, and thls spark-gap, along with the condenser C,transformer-primary p, and inductance L, forms an oscillating circuit ofver short period or very high frequency, as Wel understood in this art.A is an aerial or radiating conductor between which and the earthlateeis connected the transformersecon ary s of the transformer whoseprimary is p. G is a spark-gap in shunt to the secondar S and forms,along with condenser C, transformer-primary p, and inductance L anoscillating circuit of very high frequency. A is a second aerialconductor between which and the earth-plate e is thetransformer-secondary s cooperating with the primary p The fre uency ofthe oscillations in the circuit C, p, i, and G depends,among otherthings, as is well understood, upon the product of the ca acity andinductance of such circuit. Similar y, the fre uenc of the oscillatingcircuit C, pQL, an G e ends upon the-product of the capacity and inuctance of such circuit. The capacity and inductance, or rather theirproduct, of the circuit C L G is taken different from that of thecircuit C, p, L, and G, so that the frequency of the electromagneticwaves radiated from the conductor A 1s different from the frequency-ofthe electromagnetic waves radiated from the conductor A. Since thecurrent supplied by the secondaries S and S are in quadrature, theoscillations for each train of waves generated in the circuit C p L Gbegin at a time earlier (or later) than the commencement of a Wave-traingenerated by the circuit C, p,

L, and G, such difierence in time amounting cycles per second. Then thewave-trams emanating from A will be dephased from the wave-trainsemanating from A by an amount corresponding with a quarter period or oneseven-hundred-and-twentieth of a second. Furthermore, theelectromagnetic waves radiated from A may be at the rate of one millioner second, while those radiated from A may he at the rate of sevenhundred and fifty thousand per second. I prefer to have the condensers Cand C of very nearly the same capacity, the inductances of the twocircuits being chosen differently in order to secure the differentfrequencies, so that both condensers will be charged to their maximumpotential in equal eriods of time, so that the spark at the ga willprecede (or succeed) the ark at G y exact y a quarter of a period 0 thecurrent sqpplied to P and P. The sparkgaps G an G are preferably similarin every respect, so that both will break down under similarcircumstances.

From the foregoing description it is seen, therefore, that by depressingthe operator s key F a plurality of series of Wave-trains aretransmitted, the wave-trains of the different series bein de based withrespect to each other and t e e ectromagnetic waves of each series havina fre uency different from the frequency 0 the e ectromagnetic waves ofany other series.

Referring to Fig. 2, A is an aerial conductor by which is receivedelectroradiant energy. P is the primary winding of a transformer and isconnected between A and the earthlate e. Across the secondary S isconnecte the self-restoring Wave-responsive device W, which controls thelocal circuit including the choke-coils f f, battery B, and primarywinding of a transformer. this arrangement for every wave-train imupon Aa current impulse passes throu the primary In the circuit of the seconary 8 there is t en a series of impulses or groups of impulses whoserate of succession depends upon the rate of succession of thewave-trains transmitted. To make such secondary circuit selective ofwave-trains succeeding each other at a certain rate only, the condenserC and the inductance L are employed to so attune such circuit. Trepresents a telephone-receiver, recording instrument, or any othertranslating device. In cases where the current in the circuit of thesecondary s is extremely faint, due to excessive distance between thetransmitting and receiving stations or for any other cause, it isreinforced by the induction-generator K.

This inductiongenerator comprises a pri-. mary wlndlng lncluded inseries in the 011131111) of s. The rotor consists of a cylinder or diskof magnetizable metal and carrying short-cireulte conductors, as wellunderstood in the electricalart. By rotating the rotor at a rate inexcess of synchronism for the frequency of the impulses or groups ofimpulses passing through its pripro erly laminatedture c.

-mary the current is reinforced or boosted.

By the arrangement shown in Fi' 2, therefore, the efficiency of awireless-to e raph receiving-system is increased, and wit a given amountof energy employed or radiated at the transmitting-station a greatereffect may be produced in, the recording instrument of the receiver orany other translating device. In Fi 3, A and A represent aerialreceiving-con uctors, between which and the earth e are seriallyconnected the inductances 9 and 10, respectively. The inductance 9, withthe aerial A, constitutes a tuned or selective re raving-conductorselective of the waves of ,one series of transmltted Wave-trams.

Similarly, the inductance 10 and aerial A are solectlve of the Waves ofanother series of wavetrains. The wave-responsive devices Wand W,preferebly self-restoring, are associated with the inductances 9 and10.. Controlled.

by W is a local'circuit including the chokeand inductance L are sochosen and adjusted as to make the circuit containing them selective ofimpulses succeeding each other at the rate. of or at a mulitple of therate of'succession of the wave-trains emitted by the transmitter shownin Fig. 1. Similarly, the wave-responsive device W controls a localcircuit including the primary of the transformer whose secondary s is inseries with the condenser C the other phase-winding of theinduction-generator K the winding Y on the core Z, and the inductance L.C and L are so chosen and adjusted as to render the circuit containingthem selective of im ulses or groups of impulses succeedin each ot or ata rate equal to or a multlple of t e rate of succession of thewave-trains emitted by the wlndin s the currents of such windings willbe amp ified or boosted and will coo erate in magnetizing the core Z.Since t e transmitted wave-trains do not overlap, but alternate witheachother, the core Z receives twice as many or a multiple of twice as manymagnetizatlons per unit of time as there are wavetrains in a singleseries per unit of time. The result is that the armature c is morepositively attracted and prevented from fluttering and the operationmore certain and effective. When the armature c is attracted, it engagesthe contact 0., thus closin a circuit through the battery b and a signatranslating or recording instrument, a Morse recorderM. The spring 11opposes the attraetionof the arma- This'application is a division of myprior application, filed July 27, 1903, and bearing Serial No. 167,129.

What I claim is 1. The method of rendering intelligible messages orsignals transmitted through the natural media in electroradiant form,which consists in transforming the received electroradiant energy intothe energy of electric currents or charges, controlling by such currentsor charges locally-generated electrical energy to produce changes orfluctuations thereof, amplifying the fluctuations or changes of saidenergy, and controlling or actuating a signal-translating instrument bythe amplified energy. 4

2. The method of rendering intelligible messages or signals transmittedthrough the natural media in electroradiant form, which consists intransforming the received electroradiant energy into the energy ofelectric currents or charges, controlling by said currents or chargesthe production of current fluctuations representing the transmittedmessages or signals, increasing or amplifying said current fluctuations,and employing said amplified or increased fluctuations to reproduce themessages or signals.

3. The method of rendering intelligible messages or signals transmittedthrough the natural media in electroradiant form, which consists intransforming the received electroradiant energy into the energy ofelectric currents or charges, controlling by said currents or chargesthe production of fluctuations of current locally generated, boosting orreinforcing said current and reproducing the messages or signals by saidboosted or reinforced current.

4. The method of rendering intelligible messages or signals transmittedthrough the natural media in electroradiant form, consists intransforming the electroradiant energy into the energy of electriccurrents or charges, controlling by said currents or charges theproduction of a fluctuating current, boosting or reinforcing saidcurrent Without destroying its message or signal representin form, andreproducing the messages or signa s by said boosted or reinforcedcurrent.

5. As an improvement in the art of reproducing signals or messagesrepresented in transmission by electroradiant energy, the step whichconsists in amplifying the current changes or fluctuations representingthe messages or signals.

In testimony whereof I have hereunto affixed my signature in thepresence of two subscribing witnesses.

- CORNELIUS D EHRET. Witnesses:

ALICE S. MARsH, ELEANOR ROBERTS.

which

